Well water problems announce themselves in predictable ways: a smell, a stain, a taste, a texture. This hub matches each symptom to its likely cause, the test that confirms it, and the treatment that actually fixes it. Start with what you’re seeing — not with what a system manufacturer wants to sell you.
Diagnose by symptom
| Symptom | Most likely cause | Confirm with | Typical fix |
|---|---|---|---|
| Rotten egg / sulfur smell | Hydrogen sulfide gas, sulfur bacteria | Smell test hot vs. cold taps + H2S test | Aeration or AIO filter; shock chlorination |
| Orange or brown stains | Dissolved (ferrous) or oxidized (ferric) iron | Lab test — iron in ppm | Iron filter (AIO / greensand); softener if <3 ppm |
| Black slime or stains | Manganese, iron bacteria | Lab test — manganese ppm | Oxidizing filter; chlorination |
| Cloudy or gritty water | Sediment, sand, silt | Visual + sediment filter inspection | Spin-down + cartridge sediment filters |
| White scale, spotted dishes | Hardness (calcium/magnesium) | Hardness test — grains per gallon | Water softener sized to your GPG |
| Blue-green stains on fixtures | Acidic water corroding copper | pH test (below 7.0) | Acid neutralizer (calcite) |
The one rule that saves you money
Never buy treatment equipment before a lab test. A $30–$150 test tells you exactly what’s in your water and at what concentration — which determines whether you need a $200 cartridge setup or a $1,800 air-injection system. Sizing a system to guessed numbers is how homeowners end up with equipment that doesn’t work. Start here: how to test well water properly.
Guides in this section
- Well water smells like rotten eggs: causes and fixes
- Iron in well water: diagnosis and removal [à publier — batch 1]
- Best iron filters for well water [à publier — batch 2]
- Best whole-house filtration systems for well water [à publier — batch 2]
- Best sulfur and odor removal systems [à publier — batch 2]
When it’s a health question, not a comfort question
Staining, smells, and scale are quality-of-life problems. Bacteria (total coliform, E. coli), nitrates, arsenic, and lead are health problems. The CDC and EPA recommend testing private wells at least annually for bacteria and nitrates. If a certified lab flags any of these, follow your state health department’s guidance — treatment for health contaminants is a different category from the comfort equipment we review here.